A ball bearing is a type of bearing that uses balls to maintain separation between the moving parts of the bearing during radial loading, thrust loading, and/or moment loading. One purpose of a ball bearing is to reduce rotational friction. Reduction of rotational friction may be achieved by using at least one raceway in each of an inner ring and an outer ring, the raceways containing a plurality of balls used to transmit loads. Usually one of the rings (either the inner ring or the outer ring) is held fixed while the other is permitted to rotate. As one of the bearing rings rotates, it causes the balls to rotate between the rings. Because the balls are rolling they have a much lower coefficient of friction than if two surfaces were sliding against each other, thereby reducing friction.